Armored grilles for vehicles conventionally provide ventilation cooling of the vehicle engine compartment while preventing projectiles such as bullets or shrapnel from passing through the grille into the vehicle. One type of armored grille is disclosed by U.S. Pat. Nos. 2,363,573 and 3,068,757 and includes louvers that are bent from an armor plate which defines an outer surface of the vehicle body. Such louvers define openings that face away from the direction from which projectiles are most likely to come. Normally, the openings defined by these louvers must be of a relatively small size in order to prevent stray or deflected projectiles from passing through the openings between the louvers upon striking the grille from the direction toward which the louvers open.
Another type of armored grille disclosed by U.S. Pat. Nos. 2,376,331, 2,397,809, and 3,901,124 includes louvers with cross-sections of curved shapes for preventing projectiles from passing along a straight trajectory through the grille. Such louvers must either be deformed or machined by a suitable operation or must be cast or extruded with the curved cross-section and, as such, the consequent cost adds to to the total cost of the vehicle.
Another type of armored grille disclosed by U.S. Pat. No. 3,504,644 includes spaced sets of louvers that cooperate to prevent any projectile moving along a straight trajectory from passing through the grille. Manufacturing such a grille requires both time and a consequent expense in providing a structure that secures and positions the spaced louvers of each set in the proper location with respect to each other.
Other air vents, and the like are disclosed by U.S. Pat. Nos. 1,374,770; 1,440,307; 1,539,509; 1,736,621; 1,899,735; 1,911,408; 1,928,013; 2,393,350; and 3,749,028.